The invention relates to techniques for displaying hand-drawn lines by a display device. More particularly, the present invention relates to systems and method for varying the size of strokes displayed by a computing device to reflect the needs and intentions of the user.
There have been a number of attempts in recent years to increase the adoption rate for pen-based computing devices. A number of laptop computers now include a stylus and displays that allows users to interact with the computer using the stylus in place of the mouse for cursor control and stroke capture. Recently, handheld computing devices such as smart phones and personal digital assistants (PDA) have also started to incorporate stylus/tablet type interfaces.
One consistent problem with stylus-based tablets is that the user experience with the stylus and tablet does not match the experience one has when interacting with a writing instrument and paper. In particular, the strokes captured by the tablet and presented back to the user typically do not have any dimensions. In contrast, when a user writes on paper, the user employs pressure and a pencil angle to affect the width of the strokes drawn. But detecting angled pressure in a stylus-based tablet system is difficult and expensive. It requires both a complicated stylus and a complicated detection and reporting system. Such requirements for sophisticated stylus and reporting systems make such systems cost prohibitive.
The inability of the prior art systems to be able to render strokes that have an appropriate width has significantly diminished the user experience and the adoption rate of such stylus-based tablets. Users tend to feel a need to write in larger strokes than they would like to in order to preserve readability, including the usual ratios of ink-filled space to empty space within and between characters and lines and this is due in part to the inability of the prior art to render lines with varying widths. Especially when taking notes, it is frustrating for the user to be unable to write characters as small as they can on paper. In contrast, when drawing circles, arrows and boxes, the user wants them to be easily viewed from a distance and desires fairly broad strokes. However, the prior art does not provide an ability to manage and modify stroke width to reflect user intentions.